Name: yyT116575 Date: 10/23/2000


JBuilder 4, dont know wich versjon..


This is a resubmit of this error by request.
Java hotspot outputs this error message when the error is really stack-
overflow. It happends when during recursion. I've included the java source. It
should be devided into three files(Test.java, sNodeList.java and sNode.java).
The class Test.java is the main class. It sorts a linked list of sNodes (nodes
containing a double value) by recursion. The class Test includes a loop that
generates the linked list. By changing the limits in the loop you should be
able to regenerate the error. The error seam to appear only near the
stackoverflow-limit (around 13500 objects..). Good luck with the debugging..

# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Error ID: 53484152454432554E54494D450E43505000D8

//Test.java - a class for testing this problem..

public class Test{

  sNodeList liste;

  public static void main(String args[]){
    Test testApp = new Test();
  }

  public Test(){

    liste = new sNodeList();
    
    //Loop that generates a linked list of sNode's
    //13500 nodes makes the hotspot crash...
        
     for (int i=0; i<13500; i++){
      double x = Math.random()*100;
      liste.addElement(new sNode(x));
    }
    
    long start = System.currentTimeMillis(); //Just timing the sorting..
    
    liste.sort(); //Sorting the list
    
    long stop = System.currentTimeMillis();
    
    long tot = stop - start;
    
    System.out.println("Objects sorted in : " + tot + "ms");

  }
}








//SNodeList.java
//A linked list of sNode - objects


public class sNodeList{

  sNode header;
  sNode tail;

  public sNodeList(){

    header = new sNode(0.0);
    tail = new sNode(0.0);
    tail.setPrev(header);
    header.setNext(tail);
  }

  public void addElement(sNode s){
    tail.getPrev().setNext(s);
    s.setNext(tail);
    s.setPrev(tail.getPrev());
    tail.setPrev(s);
  }

  public String toString(){
    String str = "";
    sNode tmpNode = header.getNext();
    while(tmpNode != tail) {
      str += tmpNode.toString() + "\n";
       tmpNode = tmpNode.getNext();}
    return str;
  }

  public void sort(){
  //Here is the call that makes trouble...
   header.getNext().sortMe(false);
    }
  public sNode getHead(){ return header; }
} //end of sNodeList class







//sNode.java

public class sNode{
private double tall;
private sNode prev;
private sNode next;

public sNode(double tall){
  this.tall = tall;
  next = null;
  prev = null;
}

public String toString() {return tall + "";}

public sNode getNext(){ return next; }

public sNode getPrev(){ return prev; }

public void setNext(sNode next){ this.next = next; }

public void setPrev(sNode prev){ this.prev = prev; }

public boolean isLast(){ return (next == null) ; }
public boolean isFirst(){ return (prev.getPrev()== null); }

//This function is recursive and object-recursive (it calls the
//same function in another object..
//It goes first to the end of the list, and then starting moving
//to the front, bubbling every object that's not sorted
//backwards (to the end of the list).


public void sortMe(boolean backward){
  if (next.isLast()) { return ; }
  if (! backward) {next.sortMe(false);} //Goes to the end of the list
  if (rCompare()) { rSwap(); sortMe(true);} //Bubbles this element if not sorted
}


public boolean rCompare(){
    if ( this.tall > next.getTall()){ return true; }
    return false;
  }


public void rSwap(){
    next.setPrev(prev);
    prev = next;
    next = next.getNext();
    next.setPrev(this);
    prev.setNext(this);
    prev.getPrev().setNext(prev);
   }

  public double getTall(){ return this.tall; }
}//End of sNode class
(Review ID: 111190)
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